Neptune Smith is a giant lobster. No, not anthropomorphic. He's just a 7' long lobster, not counting the 4' reach from his claws). He is either the child of a kaiju lobster empire deep in the ocean or a mutation that gained sentience and the power of speech pulling an elaborate con. He's not exactly brilliant by human standards but he's got deep cunning and a strong survival sense that comes from being very old - while his legal status has him in his early 30's he's more likely over 300.
Neptune hasn't appeared yet: he's going to crawl out of the Haven docks and cause havoc, perhaps precipitating the formation of the super-team, but by the time the heroes arrive it will be difficult to judge who started it. Neptune will slip into the bay. He will return later in a time/place less likely to cause havoc to treat with the local authorities with not just his story but a vast supply of gold pulled up from sunken treasure vessels and a request to start is education at Yale.
Money heals many wounds, and Neptune will soon be scheming from Haven harbor, Long Island Sound, and the halls of the Ivy League. Every once in a while, he picks a fight with the heroes for no good reason and then hides behind his diplomatic immunity or some incomprehensible biological imperative. His personal fortune pays for any collateral damage. No one knows why he does this: maybe it is part of his kaiju nature, maybe he needs the force of their blows to weaken his skin before he molts, maybe the giant lobster is just an asshole. By he is insanely strong, difficult to hurt, and has enough speed an accuracy to be a threat to the heroes.
Creation Notes
Another villain for the whole team, another 1 on the powers roll. I put the first on skills and two on powers and finally got what I needed for a proper super strong character. OK, I actually didn't roll animal powers, I got water breathing, but since that immediately went to "lets super charge water breathing to make a Namor like prickly jerk with diplomatic immunity" I decided it was easier to just move it to Animal/Plant powers with maximum number of powers and make that Heightened Strength bonus at maximum. Having the backgrounds kick up Inheritor and Education while he also had Reduced Intelligence, but the level training rolls had him maximize his Int, led to the insane and delightful (to me) idea that he's an actual giant lobster, but also attending Yale with a fat wad of pirate gold.
Wecome to comics, people.